Clever, story-telling rendition of a upbeat tune.
If there's any song in the audio portal that's screaming for a flash animation to base itself on, it's this. When I hear this song, it tells me a story - the story of Mario's journey across many strange worlds, through a dangerous castle, and to a up-front confrontation with a large, fire-breathing Koopa to save the princess. *cough* Anyway, this is the type of music that flowingly tells an entriguing story (Rhapsody in Blue, for example). And it rocks.
Advice... well, if you ask me, I think the "evil castle" portion and the beginning part take a bit long, compared to the rest of it. Not enough of the fun-filled middle - the GOOD stuff, ya know? And I think the ending could've been more dynamic, rather than a 5-second happy ending.
Regardless, this deserves nothing less of an 8 outta 10. It's a well-made piece, and it really fuels the imagination. I'm a big fan of your work and I hope you continue. ^^
-Patrick H.